New DL2 User

hi,
I have a tour starting in April, with a Hog 3, Conventionnal, Moving Fixtures and 4 DL2. I will use DL2 for first time on this tour i i have some questions.

1- why on manuel there 3 Modes (Standard, Dual, Single) and only one lib with 94 channels (single mode), or must i patch 1 DL2 Graphic by DL2 for single mode 2 DL2 Graphic by DL2 for Dual mode and 3 DL2 Graphic by DL2 for single mode?

2- What is the best way: using DMX 512 or ArtNET

3- Why can't we directly networking DL2 and HOG III?

That all for today:D

Thanks
Steph